Porous metallic type



. A9 3%, 1940. I c. N. LOHREY 2,199,265,

PoRoUs METALLIC TYPE Filed July 9, 1938 Carl N. Llu'ey Inventor His Attorney sates amazes I roaons METALLIC 'rrrs Application July 9, 1938, Serial No.

6 Claims.

This invention relates to printing members and more particularly to impregnated printing members of porous metallic structure.

The principal object of this invention is to provide type; type-wheels and other printing members of porous metallic structure wettable by and capable of absorbing a relatively large amount of liquid substance, such as ink or sensitlzing fluids, which is available for rendering a great number of inked or sensitized impressions without replenishment of the supply.

Another object of the invention is to provide an ink absorbing metallic printing member of highly porous construction molded of powdered metals and a 'subliming substance which is re-. moved in a sintering operation.

Another object of the invention is to provide a metallic printing member of porous construction impregnated with absorbed ink, whereby the ink which has been transferred from the pores on the type face to the material receiving the impression, on the last printing operation, is replaced from the absorbed inki supply by capillary diffusion.

Another object of the invention is to provide a metallic printing member of ink porous construction possessing the qualities of hardness, rigidity, and malleability.

Another object of the invention is to provide a porous metallic conductor of ink having a porous printing face integral therewith, said pores being invisible to the unaided eye.

Another object of the invention is to provide an ink impregnated metallic type member of porous structure which is kept evenly saturated from a self-contained ink supply, by capillary diffusion. r

Another object of the invention is to provide a porous metallic'type wheel having a self-enclosed ink well,.said ink being conducted to the type face by interconnecting capillary pores.

Another object of the invention is to provide type of porous metallic structure, that may inked from inside the type face.

Another object of the invention is to provide a metallic type that will absorb and hold a supply of ink sufficient for a great number of impressions, which ink may be replaced by absorption when exhausted.

With these and incidental objects in view, the

- invention includes certain novel features of construction and combinations of parts, the essential elements of which are set forth in appended claims and a preferred form or embodiment of which is hereinafter described with reference to the drawing which accompanies and forms a part of this specification.

0f said drawing:

Fig. 1 is a perspective wheel having a well for view of a. typical fluids enclosed therein.

ink removed from the capillary diffusing by capillary action,

A mazes PATENT OFFl Ohio, asslgnor to The Dayton, Ohio,

Fig. 2 is a cross-sectioa-through the wheelshown in Fig. 1, perpendicular to its axis of rotation.

Fig. 3 is a vertical cross-section through a printing member mounted in a handle.

Fig; 4 represents the type levers, type basket and platen of a typical typewriter, showing a wick method of saturating porous type.

The application of ink to the printing face of metallic type has heretofore required contact of with an inking surface after every im-= because all of the ink or nearly all of type face is transferred to the the impression is'made. Methods have been devised to overcome the necessity of inkingsuch type on each inked impression among which are the use-of an inked ribbon on a sheet of carbon paper interposed between the type and the record material. In such methods using an interposed inking substance, the impression is faulty due to the thickness of the material soplaced between the type and the material to be.printed upon.

This invention provides a method of supplying ink to type faces from an ink supply contained in the pores of or conducted through pores ofthe body of the type, makin it unnecessary to ink the type faces on each printing operation or to have an intervening ink carrying material between the type and the record material. The printing face is constantly replaced from within the type member by a action.

The material used in the preferred embodiment of spplicants invention is composed of metal of a hardness comparable to that ordinarily used for metal type but having therein interconnecting capillary pores capable of absorbing and conducting fluids. The absorbed fluids are retained in the body pores of the type except that the surface film may be transferred to material used in printing by an ordinary printing operation. The ink re-. moved from the pores opening on the type face is then restored by capillary action which tends constantly to diffuse the absorbed fluid evenly throughout the type body. 1

'The method of manufactiu'lng porous metallic structures is well known, the metals used having diflerent characteristics of hardness, porosity,v and differing-as to the wetting action of fluids. The particular method outlined hereinafter as the preferred form of the invention uses metals which produce a h d porous structure, wet by, and, being porous1adapted to absorb dye inks. The following method of manufacture is typical the type pression, the ink on the printed material when but neither the materials nor the method of JUNl61942.

metal, and its ink from the surface.

Lid

action to wetting must suit the fluid to be used Manufacture of porous metallic type suitable for absorbing ink the approximate analysis of Monel metal, has,

been found most suitable for use with dye inks as it is wettable by such fluids, absorbs a considerable quantity oi. them, and is hard enough to resist wear.

A mixture of powdered copper and powdered nickel in the proportions stated is molded under great pressure in molds formed so that the type members produced have impressed thereon the characters desired. The type members so molded may be further treated by sintering in an inert gas to perfect the union of the adjacent granules of metal by heat. There will be left throughout the molded. and 'sintered product a multitude of interconnecting pores capable of absorbing dye To render the molded structure even more porous, some material that sublimates in the presence of heat may be added in the form of powder, to the powdered copper and powdered nickel so that when the. sintering operation is completed the space formerly occupied by the sublimed material serves as additional pore space for the storage of ink. The molded product may be struck by a forming tool to shape it without destroying its porosity.

The pores so produced extend to the surface of the molded product and consequently the fluid at the open ends of the said pores are subject to ordinary surface tension phenomena. The result is that the fluids absorbed by the molded product will not be dissipated unless the surface film is broken. by a printing impression, in which event a portion of the surface film will be transferred to the article to be printed. This removed surface fllm is restored at once by the diffusion of the ink contained in the pores, due to capillary action.

The pores so formed are so small as to be invisible to the unaided eye. The small size of the pores allows only a small portion of ink to be transferred on a. printing operation, eliminating any possibility of smudging or blotting. The capillary forces in such small pores are so great as to hold the fluid in the pores against gravitational force, and the moving forces caused by rotation or hammering normal to printing operations.

Means of supplying typamembers rnith fluids The wheel form of embodiment of the invention is illustrated in Figs. 1 and 2 which represent a porous metallic type wheel l0 mounted on a shaft ll having a plurality of type faces l2 on its circumference.

shown in Fig. 2. A plug I4 is provided giving access to the font from the circumference of the wheel for filling with fluid. In this particular form the fluids saturate the porous printing wheel by contact therewith. Capillary forces acting on the surface film formed at the external pore openings keep the fluid within the wheel, except when the surface film is broken by contact with the material to be printed.

A modifled form of embodiment of the inven- Within the body of the wheel is an annular font l3 adapted to hold fluids as- A removable handle it is provided to protect the hands of the user from contact with the printing member. With this construction the member i5 is used repeatedly until exhausted of fluid and then is resaturated.

Another desirable embodiment is shown in Fig. 4 wherein the porous metallic type ii is fastened to the type levers E8 of a typical typewriter. Normally the body of the type ll rests on a wick it which is half submerged in fluid it held in a reservoir 26. The reservoir and wick take the place of the usual type basket. The wick I9 is saturated with the fluid and whatever fluid is removed from the type body by the type face in the printing operation is replenished by the wick as the type rests thereon. A screen support 22 maintains the wick in a partially submerged condition to prevent splashing. A platen 23 is illustrated as holding record material 24 in the usual manner. In this construction the same wick can serve a plurality of printing members.

The ink used with porous type should preferably be non-volatile and non-clogging.

It is to be understood that applicant is not confining his invention to the particular combi-- nation of metals named nor their use solely with the fluids mentioned, although the metals mentioned have been found particularly suited to be used with dye inks.

While the form of mechanism herein shown and described is admirably adapted to fulfill the objects primarily stated, it is to be understood that itis not'intended to confine the invention to the one form or embodiment herein..disclosed,.

for it is susceptible of embodiment in various forms all coming within the scope of the claims a rigid structure is formed.

2. As a new article of manufacture, a product produced in accordance with the method of claim 1.

3. The method of making porous printing type I consisting of mixing seven parts of powdered nickel and three parts of powdered copper; molding the mixture under great pressure until a rigid structure is formed; and sintering the molded body in an inert gas. I

4. As a new article of manufacture, a product produced in accordance with the method of claim 3.

5. The method of making porous printing type consisting of mixing seven parts of powdered nickel, three parts of powdered copper, and a powdered subliming material; molding the mixture under great pressure; and sinterlng the molded body in an inert gas to perfect the union of the constituent metal particles and to vaporize and expel the subliming material.

6. As a new article of manufacture, a product produced in accordance with the method of 

